Influence of Diamond-Like Carbon Film on the Durability of Hydrophobic Structure of Aluminum Alloy

To improve the hydrophobicity and corrosion resistance of 2024 aluminum alloy, electrochemical etching and plasma-enhanced chemical vapor deposition(PECVD) technologies were used to prepare micro-nano embossed hydrophobic structure and diamond-like carbon(DLC) film on its surface. Contact angle measuring instrument, electrochemical workstation and erosion experiment were used to study the hydrophobicity, corrosion resistance and hydrophobic durability of 2024 aluminum alloy under different treatment processes, and the corresponding mechanism was also discussed. The results indicate that the static contact angle results of 2024 aluminum alloy with water can reach more than 130° after electrochemical etching, and the hydrophobic performance was improved significantly. Impedance results show that the impedance modulus after electrochemical etching was increased by about 8 times, the corrosion current density was decreased by two orders of magnitude, and the corrosion resistance was significantly improved. After etching, the aluminum alloy plated with an amorphous inert DLC film has an impedance modulus of 1.016×10⁷Ω·cm^-2, which can effectively hinder the charge transfer and ion transport charge transfer in the corrosion process, and significantly extend the durability of the hydrophobic structure.